On the WordCamp San Francisco website (the event took place from August 12 to 14, 2011) you will find plenty of great video recordings of the individual talks, a good way to catch up on the latest trends and topics around WordPress. I found “Responsive Web Design” by Sara Cannon, “Options for a Multilingual Site” by Shannon Smith and “Awesome Up Your Boring Theme: WordPress Post Formats” by Ian Stewart especially interesting.